@book { VersicherungunternehmerischerRisiken,
    title = "Versicherung unternehmerischer Risiken",
    author = "Björn {Bogner}",
    year = "2009",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1107011"
}